Following an uneven second season of ABC's REVENGE, showrunner Mike Kelley has stepped down.The executive producer of the network's primetime soap had been with the series since it debuted to strong reviews and solid ratings in the fall of 2011. Its sophomore run has not been as successful even after a move to Sunday nights. Current executive producer Sunil Nayar is expected to take over during the show's third season, if the likely renewal happens.